Folinic acid in colorectal cancer: esquire or fellow knight? Real-world results from a mono institutional, retrospective study

The stock of therapeutic weapons available in metastatic colorectal cancer (mCRC) has been progressively grown over the years, with improving both survival and patients' clinical outcome: notwithstanding advances in the knowledge of mCRC biology, as well as advances in treatment, fluoropyrimidine antimetabolite drugs have been for 30 years the mainstay of chemotherapy protocols for this malignancy. 5-Fluorouracil (5FU) seems to act differently depending on administration method: elastomer-mediated continuous infusion better inhibits Thymidylate Synthase (TS), an enzyme playing a pivotal role in DNA synthetic pathway. TS overexpression is an acknowledged poor prognosis predicting factor. The simultaneous combination of 5FU and folinate salt synergistically strengthens fluorouracil cytotoxic effect. In our experience, levofolinate and 5FU together in continuous infusion prolong progression free survival of patients suffering from mCRC, moreover decreasing death risk and showing a clear clinical benefit for patients, irrespective of RAS mutational status, primitive tumor side and metastases surgery.